TERMINAL ADAPTER

PROBLEM TO BE SOLVED: To provide a terminal adapter where dialing operations for setting whether or not a caller number is informed to an opposite party are reduced. SOLUTION: A PB(push button) telephone set 4 is connected to an analog port part 11 of a terminal adapter 1. A PB signal detection part 12 receives a dial number inputted from the PB telephone set 4. A control part 16 determines whether or not a caller number is informed to an opposite party from the contents of the dial number that the PB signal detection part 12 receives and writes the history of the notice/non-notice of the caller number in a memory part 15. The control part 16 outputs the dial number, where a header number which switches setting whether or not the caller number is informed, if needed to the telephone number of the opposite party to an ISDN (integrated service digital network) circuit side from an S/T interface part 14, by adjusting it to a more frequent case between cases when the caller number is informed from the history of the memory part 15 and when it is not informed.